Polyphase copolymerization of styrene compounds with drying oil fatty acid compounds



Unite States POLYPHASE COPOLYMERIZATION OF STYRENE COMPOUNDS WITH DRYING OIL FATTY ACID COB [POUNDS No Drawing. Application December 14, 1953 Serial No. 398,194

Claims priority, application Netherlands December 19, 1952 3 Claims. (Cl. 260-23) This invention relates to a process for the copolymerization of styrenes with drying oil fatty acid compounds to obtain products which dry in air.

It is well known that products which are suitable for paints and varnishes can be obtained by copolymerizing a styrene compound with a drying oil fatty acid compound, for example, a drying oil or fatty. acid derived therefrom, a drying oil-modified alkyd resin, or a drying oilmodified polymeric polyhydric alcohol. The copolymers obtained by the prior art processes often have an-appearance of turbidity caused by soluble, high molecular products with a high content of styrene. These high molecular products are hereinafter referred to -as;polystyrenes although they do not consist exclusively of styrene compounds. The resulting copolymersare'not as soluble in aliphatic solvents as is desirable for general use in paints and varnishes. been proposed for effecting the copolymerization Without the formation of substantial amounts ofundesirable polystyrene compounds. However, these processes generally have various disadvantages. For example, the reaction time is often very long, amounting to to hours or more. The necessity of adding large quantities of solvent is another disadvantage of the known processes. It has also been proposed to employ amixture of styrene and alpha-methyl styrene, however, the use of such a mixture is much more expensive than the usev In all of the of the cheaper component, styrene, alone. prior art processes the coploymerization has been carried out employing the styrene compound inthe liquid state.

In accordance with the present invention, it has now been found that improved copolymers of styrene compounds with drying oil fatty acid compound can be obtained by carrying out the copolymerization reaction employing the styrene compound inthe vapor state.

According to a preferred embodiment of. the present invention, improved copolymers of a. styrene compound, preferably styrene, anda drying oil or drying oil fatty acid, can be obtained by effecting the copolymerization employing the styrene compound in the vapor state.

In carrying out the copolymerization reaction in accordance with the present invention, the styrene compound is generally vaporized in a stream of an inert gas and then passed through the unsaturated fatty acid compound which, is maintained at a temperature of between about 150 C. and the boiling point of the fatty acid compound, preferably between about 200 C. and about 300 C. If necessary or desirable, the fatty acid compound can be dissolvedin a suitable solvent. The copolymerization reaction can be carried out with or without: a conventional polymerization catalyst.

The inert carrying gas should preferably not be soluble in the fatty acid compound to any considerable extent so that any unreacted styrene compound can be removed Several processes have atent O ICC from the reaction mixture by means of the carrying gas. In general, nitrogen is a satisfactory carrying gas.

Care must be taken to prevent reflux in the-reaction mixture of any of the styrene compounds which may have condensed to the liquid state. Such reflux can be avoided by heating the entire reaction vessel, for example, by completely immersing the reaction vessel in a liquid bath. It is also possible to design the reaction vessel to provide for the removal of liquefied styrene compound. For example, the reaction vessel can be provided with a channel near the upper, unheated portion, in which channel the. liquid styrene compound collects and from which the collected liquid is. discharged.

In order to insure a smooth reaction, it is generally desirable to employ a considerable excess ofthe styrene compound. Preferably from about'lO to about 20 times the amount of the styrene compound which can be absorbed by the unsaturated fatty acid compound is employed. The recovered, unreacted styrene compound can be recycled to the copolymerization zone. In somecases, it may be desirable to substantially completely depo1ymerize the unreacted styrene'compound prior to reuse. Generally, passage ofthevaporized styrene compound through the liquid unsaturated'fatty acid compound is continued for a time. sufiicient to. provide a copolymer product containing from about 10% to: about by weight of the styrene compound.

The process of the present invention is suitable for either batch or continuous operation.

The styrene compounds which are suitable for use in the present invention are preferably those which conform to the following general formula:

wherein R is the hydrogen atom or a lower alkyl group of not more than 2 carbon atoms, Xis the hydrogen atom, the hydroxyl group, a halogen. atom, a lower alkoxyl group of not more than 3 carbonxatoms, or a lower alkyl group of not morethan 3 carbon atoms, and n is an integer of from 1 to 5; Typical suitable styrene compounds include: styrene, alphaemethyl styrene, para-methylstyrene, parax-chlorostyrene, para-fluorostyrene, metachlorostyrene, meta-fluorostyrene, metaand para-trichloromethylstyrenes, metaand paratrifiuoromethylstyrene, orthoand meta-hydroxystyrenes, methoxy-styrenes, and the like.

The present invention is applicable to the styrenation of drying oil ,fatty acid compounds which term is used to include drying oils, drying oil-fatty acids, synthetic drying oils, and drying oil fatty acidor drying oilmodifiedsynthetic resinous product such as drying toil fatty acid-modified alkyd resins andtdrying oil acid-modifiedcondensation. products of polyhydric phenols with polyfunctional alcohol-contributing reactants, such as polyhalohydrins, epihalohydrins, or polyepoxides. Typical representative drying oil fatty acid compounds which can be employed in the process of the present invention include: tung oil, linseed oil, soybean oil, dehydrated castor oil, perilla oil, fish oil such as sardine oils, oiticica oil, cottonseed oil, hempseed oil, poppyseed oil, safilower oil, and sunflower oil; fatty acids derived from the aforementioned drying-oils; partially polymerized drying oils such as partially polymerized linseed oiltoxidiieddryiug oils such as oxidizedsoybean oil; synthetic drying oils such as are obtained by the esterification of fatty acids derived from aforementioned-drying oils With'polyhydric alcohols, for' example, glycerol, pentaerythritol, man'- nitol,-sorbitol, and polypentaerythritol; drying oil-alkyd resins such as are obtained by the reaction of a drying oil fatty acid with a polyhydric alcohol such as glycerol, diethylene glycol, pentaerythritol, dipentaerythritol, sorbitol, mannitol, trihydroxymethylaminomethane, trimethyl- 'olpropane, etc., and a polycarboxylic acid such as maleic anhydride, fumeric acid, phthalic acid, adipic acid, sebacic acid, cyclopentadiene-maleic'anhydride adduct, terpene-maleic acid adduct, 4-cyclohexene-l,2-dicarboxylic acid, etc.; and drying oil fatty acid-modified condensation products of polyhydric phenols such as resorcinol, hydroquinone. catechol, phloroglucinol, bisphenol, p,pdihydroxy benzophenone; o,p,op'-tetrahydroxydiphenyl dimethyl methane, hematoxylin, polyhydric anthracenes, polyhydric naphthalenes, etc.; with polyhalohydrins such as glycerol dichlorhydrin, beta-methyl glycerol dichlorhydrin, epihalohydrins such as epichlorhydrin, epibromhydrin, epihalohydrins of mannitol, sorbital, and erythritol, or polyepoxides such as bis-(2,3-epoxypropyl)ether,

butylene dioxide, diepoxides of mannitol, sorbitol, etc.;

and the like drying oil fatty acid compounds. Drying oils and drying oil fatty acids are preferred for use in the present process.

The invention is illustrated by the following example which is not to be construed as limiting the specification and claims in any manner:

EXAMPLE A series of tests were carried out as described below in which linseed oil was copolymerized with styrene under varying conditions.

convert or remove the last traces of monomer styrene.

The mixture was then allowed to cool. The nitrogen stream was passed through the product during the continued heating and the subsequent cooling.

The amount of styrene which had reacted with the linseed oil was determined by weighing the oil before and after the reaction. The clarity of the product obtained was assessed and its viscosity and refractive index measured. The product was further examined for polystyrene content in accordance with the method described by B. Bokhout, Chem. Weekbl. 46, 836 (1950). The product was heated for two hours, using a reflux cooler, together with a sufficient quantity of a solution of one part of KOH in 3 parts of ethyl alcohol and 7 parts of toluene, to provide a molar excess quantity of 10% KOH with respect to the esterified fatty acid. After the solvents had been distilled oh, the saponification products obtained proved, in each case, to be substantially completely soluble in methyl alcohol. No polystyrene had separated oif. The results of the tests are summerized A measured amount of hnseed 011 was placed in a reacm Table I.

Table I Properties of Products Obtained Styrene Nitrogen Quantity Added Duration Stream Reaction Tempera- Linseed (Parts by of Reae- (Parts by Styrene ture 0.) Oil (Parts Weight] tion Volume] Content Viscosity by Weight) Hour) (Hours) Hour) (Peficent (Pulses) my" Appearance 17 Weight) 40 0 4 3 0 2 1. 4813 Clear. 40 30 4 3 13. 4 56 1. 5088 Do. 40 60 4 3 19. 5 191 1. 5173 Do. 40 60 4 3 20.0 219 1. 5183 D0. 40 90 4 3 20. 8 225 1. 5193 Very slight turbidity. 40 120 4 3 21. 7 315 1. 5207 Slight turbidity. 40 6O 4 10 8. 2 57 1. 5051 Clear. 40 60 4 8 12. 7 97 1. 5092 Do. 40 6D 4 5 15. 5 178 1. 5145 Do. 40 6D 4 3 19. 5 191 1. 5173 D0. 40 60 4 2 23.0 390 1.5219 Very slight opalescence. 40 60 4 1 28. 0 1, 070 1, 6284 Slight opalescence. 40 60 2 3 8. 1 10 1. 5001 Clear. 40 60 3 3 14. 1 49 1. 5099 D0. 40 60 4 3 19. 5 191 1. 5173 Do. 40 60 6 3 21. 9 349 1. 6209 D0. 60 7 3 28. 7 982 1. 5290 Do. Z0 60 4 3 20. 0 532 1. 5200 D0. :0 60 4 3 18. 4 1, 800 1. 5230 Do. 70 60 4 3 14. 6 6, 000 1. 526 D0.

tion vessel which was provided with an annular channel at its upper portion and with a narrow vapor inlet near its base. The reaction vessel was placed in a molten metal bath. The linseed oil was heated to the desired temperature while a stream of nitrogen was passed therethrough at a constant rate. In order to remove traces of moisture and to insure decomposition of any peroxide present, addition of styrene was not begun until 15 minutes after the linseed oil had reached the reaction temperature. Styrene was added dropwise at a constant rate to the stream of nitrogen, the flow rate of which was maintained constant throughout the entire operation. As the resulting mixture was passed through the vapor inlet tube which was partially immersed in the molten metal bath, the styrene was vaporized. The resulting mixture of vaporized styrene and nitrogen was then passed through the linseed oil in the reaction vessel. The gas stream escaping from the liquid linseed oil and consisting of We claim as our invention:

1. A process for copolymerizing a styrene compound of the formula 5 group being attached to hydrogen, with a drying oil' selected from the group consisting of unsaturated fatty acid glycerides and fatty acids derived from such glycerides, which comprises heating the said drying oil in the liquid phase to a temperature between 150 C. and 300 C.,

vaporizing the styrene compound in an inert gas and passing the gaseous mixture into and through the body of the heated liquid drying oil.

2. A process as in claim 1 wherein the styrene compound is styrene.

3. A process as in claim 1 wherein the drying oil is linseed oil.

References Cited in the file of this patent UNITED STATES PATENTS Aylesworth June 18, 1912 Heuer Nov. 7, 1939 OTHER REFERENCES Hewitt et al.: J. Oil and Colour Chemists Assn., June 1946, pp. 109-128.

Boundy: Styrene, Its Polymers, Copolymers and Deriv., 1952, pp. 816-817.

Varnish Constituents, Chatfield, Leonard Hill Limited, London, 1953, page 120. 

1. A PROCESS FOR COPOLYMERIZING A STYRENE COMPOUND OF THE FORMULA 